• A survey on maritime fleet size and mix problems 

      Pantuso, Giovanni; Fagerholt, Kjetil; Hvattum, Lars Magnus (Journal article, 2013)
      This paper presents a literature survey on the fleet size and mix problem in maritime transportation. Fluctuations in the shipping market and frequent mismatches between fleet capacities and demands highlight the relevance ...
    • A Traveling Salesman Problem with Pickups and Deliveries and Stochastic Travel Times: An Application from Chemical Shipping 

      Elgesem, Aurora Smith; Skogen, Eline Sophie; Wang, Xin; Fagerholt, Kjetil (Journal article; Peer reviewed, 2018)
      This paper introduces a single-ship routing problem with stochastic travel times that is faced by a chemical shipping company in the Port of Houston. We take into explicit consideration the uncertain waiting times associated ...
    • Adaptive large neighborhood search heuristics for multi-tier service deployment problems in clouds 

      Gullhav, Anders Nordby; Cordeau, Jean-Francois; Hvattum, Lars Magnus; Nygreen, Bjørn (Journal article; Peer reviewed, 2016)
      This paper proposes adaptive large neighborhood search (ALNS) heuristics for two service deployment problems in a cloud computing context. The problems under study consider the deployment problem of a provider of ...
    • Bidding in sequential electricity markets: The Nordic case 

      Boomsma, Trine Krogh; Juul, Nina; Fleten, Stein-Erik (Journal article; Peer reviewed, 2014)
      For electricity market participants trading in sequential markets with differences in price levels and risk exposure, it is relevant to analyze the potential of coordinated bidding. We consider a Nordic power producer who ...
    • A column generation heuristic for the dynamic bicycle rebalancing problem 

      Gleditsch, Marte; Kristine, Hagen; Bakker, Steffen J.; Andersson, Henrik; Fagerholt, Kjetil (Peer reviewed; Journal article, 2022)
      Public bicycle sharing systems are becoming an essential part of the future urban mobility system. Real-time monitoring of the system state through sensors on bicycles and/or stations gives possibilities for advanced ...
    • Dynamic job assignment: A column generation approach with an application to surgery allocation 

      Range, Troels Martin; Kozlowski, Dawid; Petersen, Niels Christian (Journal article; Peer reviewed, 2018)
      We consider the assignment of jobs to heterogeneous agents in a dynamic system with a rolling time horizon. An example is a hospital operating theatre where the jobs are surgeries and the agents are the surgeons. The paper ...
    • An exact solution method for the capacitated item-sharing and crowdshipping problem 

      Behrend, Moritz; Meisel, Frank; Fagerholt, Kjetil; Andersson, Henrik (Peer reviewed; Journal article, 2019)
      The item-sharing and crowdshipping problem combines two concepts of the sharing economy, namely item-sharing and crowdshipping. Item-sharing is about renting items among members of a sharing community. Crowdshipping addresses ...
    • Hybrid heuristics for a short sea inventory routing problem 

      Agra, Agostinho; Christiansen, Marielle; Delgado, Alexandrino; Simonetti, Luidi (Journal article; Peer reviewed, 2014)
      We consider a short sea fuel oil distribution problem where an oil company is responsible for the routing and scheduling of ships between ports such that the demand for various fuel oil products is satisfied during the ...
    • An improved formulation for the inventory routing problem with time-varying demands 

      Skålnes, Jørgen; Andersson, Henrik; Desaulniers, Guy; Stålhane, Magnus (Journal article; Peer reviewed, 2022)
      The Inventory Routing Problem (IRP) is a broad class of complex routing problems where the quanti- ties of delivered products must also be determined. In this paper, we consider the classic IRP where a single supplier must ...
    • Improved models for a single vehicle continuous-time inventory routing problem with pickups and deliveries 

      Agra, Agostinho; Christiansen, Marielle; Wolsey, Laurence (Peer reviewed; Journal article, 2022)
      We consider an inventory routing problem in which a single vehicle is responsible for the transport of a commodity from a set of supply locations to a set of demand locations. At each location the inventory must be kept ...
    • Industrial and Tramp Ship Routing Problems: Closing the Gap for Real-Scale Instances 

      Homsi, Gabriel; Martinelli, Rafael; Vidal, Thibaut; Fagerholt, Kjetil (Peer reviewed; Journal article, 2019)
      Recent studies in maritime logistics have introduced a general ship routing problem and a benchmark suite based on real shipping segments, considering pickups and deliveries, cargo selection, ship-dependent starting ...
    • Inventory routing with pickups and deliveries 

      Archetti, Claudia; Christiansen, Marielle; Speranza, M. Grazia (Journal article; Peer reviewed, 2018)
      This paper introduces a class of problems which integrate pickup and delivery vehicle routing problems (PDPs) and inventory management, and we call them inventory routing problems with pickups and deliveries (IRP-PD). We ...
    • Joint relocation and pricing in electric car-sharing systems 

      Eilertsen, Ulrik; Falck-Pedersen, Olav Mattias; Henriksen, Jone Våge; Fagerholt, Kjetil; Pantuso, Giovanni (Journal article; Peer reviewed, 2023)
      In this paper we study the integrated planning problem of determining car-sharing prices between zones of the operating area and routing employees (operators) to relocate cars in preparation for future uncertain demand. ...
    • Maritime crude oil transportation – A split pickup and split delivery problem 

      Hennig, Frank; Nygreen, Bjørn; Christiansen, Marielle; Fagerholt, Kjetil; Furman, Kevin C; Song, Jinhwa; Kocis, Gary R; Warrick, Philip H (Journal article; Peer reviewed, 2012)
      The maritime oil tanker routing and scheduling problem is known to the literature since before 1950. In the presented problem, oil tankers transport crude oil from supply points to demand locations around the globe. The ...
    • Network design with route planning for battery electric high-speed passenger vessel services 

      Havre, Håkon Furnes; Lien, Ulrik; Ness, Mattias Myklebust; Fagerholt, Kjetil; Rødseth, Kenneth Løvold (Peer reviewed; Journal article, 2023)
      This paper studies the Zero Emission passenger Vessel Service Network Design Problem (ZEVSNDP) in order to investigate how technical and economic challenges related to diffusion of battery electric vessels can be alleviated ...
    • New benchmark instances for the inventory routing problem 

      Skålnes, Jørgen; Ben Ahmed, Mohamed; Hvattum, Lars Magnus; Stålhane, Magnus (Journal article; Peer reviewed, 2023)
      The existing sets of benchmark instances for the inventory routing problem (IRP) have been beneficial for investigating and illustrating the properties of the problem. However, they possess certain features and design ...
    • Risk aversion in imperfect natural gas markets 

      Egging, Ruud; Pichler, Alois; Kalvø, Øyvind Iversen; Walle-Hansen, Thomas Meyer (Journal article; Peer reviewed, 2017)
      This paper presents a natural gas market equilibrium model that considers uncertainty in shale gas reserve exploration. Risk aversion is modeled using a risk measure known as the Average Value-at-Risk (also referred to as ...
    • Solving oligopolistic equilibrium problems with convex optimization 

      Egging-Bratseth, Ruud; Baltensperger, Tobias; Tomasgard, Asgeir (Peer reviewed; Journal article, 2020)
      The approach of choice to analyze markets with oligopolistic competition has traditionally been complementarity modeling. In this paper we show that the majority of partial equilibrium models under imperfect competition ...
    • Stochastic master surgery scheduling 

      Bovim, Thomas; Christiansen, Marielle; Gullhav, Anders Nordby; Range, Troels Martin; Hellemo, Lars (Journal article; Peer reviewed, 2020)
      The aim of the Master Surgery Scheduling Problem (MSSP) is to schedule the medical specialties to the different operating rooms available, such that surgeries may be performed efficiently. We consider a MSSP where elective ...
    • Stochastic short-term hydropower planning with inflow scenario trees 

      Seguin, Sara; Fleten, Stein-Erik; Cote, Pascal; Pichler, Alois; Audet, Charles (Journal article; Peer reviewed, 2016)
      This paper presents an optimization approach to solve the short-term hydropower unit commitment and loading problem with uncertain inflows. A scenario tree is built based on a forecasted fan of inflows, which is developed ...